I’ll flag one thing which is that the page table stuff mentioned is unlikely something rust can protect you against - if you set up the wrong memory mapping that’s a higher level logic bug that would make rust unsound and result in weird failures. Rust can only protect you within the bounds of the memory model it defines for its abstract machine.
There's probably a lot of other memory bugs though. The first thing I looked at was the shell, and almost immediately I spotted an out of bounds write (input[n] = '\0' where n could be sizeof(input)).
For sure. I’m highlighting the nastier parts of the system that Rust can’t help with. I love Rust but it’s important to understand its limitations, particularly for something like OS development. There’s a similar way to make Rust unsafe using 100% safe Rust where you poke /proc/self/mem to violate memory safety using safe IO :).